Method and system for controlling traffic over a computer network

Abstract

A rate limiter incorporated in a server connected to a network. The rate limiter is adapted to reduce congestion in the network in response to a congestion notification message. The server is adapted to send packets over the network. The rate limiter includes at least one of: a server rate limiter engine adapted to rate limit the packets in response to the server; a virtual machine rate limiter engine adapted to rate limit the packets in response to a virtual machine associated with the packets, the virtual machine hosted by the server; a flow rate limiter engine adapted to rate limit the packets in response to a flow associated with the packets; the flow being one of a plurality of flows transporting packets over the network; and a transmit engine adapted to rate limit the packets in response to a virtual pipe of the network for transmitting the packets.

Description

FIELD OF THE INVENTION[0001]This invention relates generally to traffic control in a computer network, and more specifically to rate limiting in response to congestion in the network.BACKGROUND OF THE INVENTION[0002]Network congestion can occur when too much data is sent through a particular link or node of a network. Such congestion may negatively affect the quality of service provided by the network. For example, it may cause queuing delays, packet losses, and blocked connections. Therefore, it is desirable to make sure that the amount of traffic passing through each node of the network does not exceed what the node can handle.[0003]A typical scenario of network congestion is illustrated in FIG. 1. As illustrated, the network includes two servers A and B 100, 102, a switch 104, and two disks T1 and T2108, 110. The number of devices shown in FIG. 1 is limited for illustration purposes only. Additional servers, switches, disks, and other types of devices may be connected to the netw...

AI Technical Summary

Benefits of technology

[0009]The use of separate rate limiter engines and profile tables with individualized allocations for each flow, virtual machine, and blade server provides an important advantage in the architecture of the ASIC, in that software or firmware can separately set the allocations. In one embodiment, a processor is only used to set initial allocations for the virtual machines, flows, and blade servers. All other operations of the rate limiter are performed by hardware. As such, the verification can be done in a short amount of time and does not negatively affect the performance of the host device.

[0010]In addition, the rate limiting features provided by embodiments of the invention allow the network to maintain a high throughput by keeping the number of dropped packets low. By identifying the flow, virtual machine, and / or blade server responsible for congestion in the network, the disclosed rate limiter is able to selectively control traffic based on the flow, the virtual machine, and / or the blade server so that flows, virtual machines, and blade servers not responsible for the congestion are not interrupted. In other words, limitations may be selectively placed, through software or firmware, on traffic for particular flows, virtual machines, and / or blade servers to accomplish network objectives under congested conditions.

Problems solved by technology

In other words, limitations may be selectively placed, through software or firmware, on traffic for particular flows, virtual machines, and / or blade servers to accomplish network objectives under congested conditions.

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